<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        /* 列表的最后一个 */
        ul li:last-of-type{
            color: blue;
        }
        /* 列表的第一个 */
        ul li:first-of-type{
            color: blueviolet;
        }
        /* 列表的第四个 */
        ul li:nth-of-type(4){
            color: greenyellow;
        }
        .container div:first-of-type div:nth-of-type(3){
            color: red;
        }
    </style>
</head>
<body>
    <ul>
        <li>111</li>
        <li>222</li>
        <li>333</li>
        <li>444</li>
        <li>555</li>
        <li>666</li>
    </ul>
    <div class="container">
        <div>
            <div>1-1</div>
            <div>1-2</div>
            <div>1-3</div>
            <div>1-4</div>
            <div>1-5</div>
        </div>
        <div>2</div>
        <div>3</div>
        <div>4</div>
        <div>5</div>
        <div>6</div>
        <div>7</div>
        <div>8</div>
        <div>9</div>
        <div>10</div>
    </div>
</body>
</html>